Junk e-mail messages - known as spam - are costing British companies £5bn a year and severely holding back the growth of the Internet as a tool for business, a new survey claims.

In addition, the rise of spam is causing instances of "cyber-stalking",
where users of the Internet find themselves bombarded by offensive e-mail from an individual.

The survey for software company Novell Inc says 75% of the e-mail users questioned said they receive up to five spam messages a day. About 15% of respondents spend up to an hour a day reading and deleting spam from their computers.

Unwanted messages

The most common types of spam are commercial messages trying to sell products or
services, it adds.

The report says: "In terms of invasion of personal space, spamming is similar
to cold calling or door-to-door selling, where the spammer attempts to enter
your home or office uninvited.

"However, spamming is much more cowardly because you cannot see or hear the
offender and you cannot tell them to go away."

Wasted time

Businesses are worst affected by the loss of employees' time and productivity
resulting from spam, the study concludes.

"At any one time, 1.4% of the UK workforce is idle because they are dealing
with spam instead of working.

"Assuming an annual UK wage bill of £368bn, handling spam is costing UK
business just over £5bn per annum."

Menace by modem

Although less common, abusive messages are the most worrying kind of unwanted e-mail. Clever
Internet users can use many ploys to disguise their identity and location in
order to subject a chosen victim to a barrage of electronic abuse.

One victim of so-called "cyber-stalking", London-based single mother Debbie
(not her real name), said she had become friends with many people online with
no problems.

Then one casual exchange of e-mail with another person became more serious -
if Debbie delayed replying, the abuser sent angry messages asking her to
respond.

These gradually became more abusive, even pornographic and violent,
over a period of six months.

"Even though I could not see or identify the abuser it was a very frightening
experience," she said.

"Eventually when I threatened legal action the e-mails stopped, but it made
me very wary of communicating over the Internet."